[英]Android MediaStore.Images.Media.getBitmap returns error
[英]MediaStore.Images.Media.getBitmap and out of memory error
我的代碼是:
public Bitmap loadPhoto(Uri uri) {
Bitmap scaled = null;
try {
scalled = Bitmap.createBitmap(
MediaStore.Images.Media.getBitmap(getContentResolver(), uri),
0,0,90, 90);
if (scaled == null) { return null; }
} catch(Exception e) { }
return scaled;
}
在這之后。 我在ImageView中顯示縮放。 每張圖片都來自設備相機。
每次,我都會收到錯誤:我從相機顯示三張照片后內存不足 。 怎么解決這個?
嘗試使用BitmapFactory來解決問題http://developer.android.com/reference/android/graphics/BitmapFactory.html
Praveen Katha的答案總是會返回null。 這是更新的答案。
這是技巧,每次使用后關閉輸入流。 輸入流意味着使用一次。 有關更多信息,請按照此答案
private static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) >= reqHeight
&& (halfWidth / inSampleSize) >= reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}
public static Bitmap decodeSampledBitmapFromUri(Context context, Uri imageUri, int reqWidth, int reqHeight) throws FileNotFoundException {
Bitmap bitmap = null;
try {
// Get input stream of the image
final BitmapFactory.Options options = new BitmapFactory.Options();
InputStream iStream = context.getContentResolver().openInputStream(imageUri);
// First decode with inJustDecodeBounds=true to check dimensions
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(iStream, null, options);
if (iStream != null) {
iStream.close();
}
iStream = context.getContentResolver().openInputStream(imageUri);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeStream(iStream, null, options);
if (iStream != null) {
iStream.close();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return bitmap;
}
MediaStore.getBitmap方法是一種便捷方法,在獲取位圖時不指定樣本大小。 如果您正在使用getBitmap(ContentResolver,Uri),並且想要使用樣本大小,只需使用ContentResolver獲取輸入流,並像平常一樣解碼位圖(首先計算樣本大小,然后使用適當的方法加載它)樣本量)。
對於那些正在尋找代碼示例的人:
private static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) >= reqHeight
&& (halfWidth / inSampleSize) >= reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}
public static Bitmap decodeSampledBitmapFromUri(Context context, Uri imageUri, int reqWidth, int reqHeight) throws FileNotFoundException {
// Get input stream of the image
final BitmapFactory.Options options = new BitmapFactory.Options();
InputStream iStream = context.getContentResolver().openInputStream(imageUri);
// First decode with inJustDecodeBounds=true to check dimensions
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(iStream, null, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeStream(iStream, null, options);
}
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